Work-piece holding device

Abstract

To provide a work-piece holding device that can quickly hold a work-piece.SOLUTION: A work-piece holding device which holds a work-piece comprises: a first rotating body in which a first rolling body is provided between a first inner ring and a first outer ring; a base stand that supports the first inner ring so that the first outer ring can freely rotate; an actuator that rotates the first outer ring; a holding arm installed on the base stand to be movable back and forth; and a transmitting body that transmits rotation force of the first outer ring to the holding arm. The work-piece holding device is further provided with an attaching bracket for attaching the actuator to the base stand, where the actuator may be turnably attached to the attaching bracket. A first outer peripheral gear is provided on an outer periphery of the first outer ring. The transmitting body comprises a transmitting gear that engages with the first outer peripheral gear. The holding arm may comprise an arm gear that engages with the transmitting gear.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a workpiece holding device used to hold a workpiece. [Background technology]

[0002] When machining a workpiece using various processing machines, the workpiece is held by a workpiece holding device. A scroll chuck (Patent Document 1) is known as a conventional workpiece holding device, in which jaws are advanced and retreated by the rotation of an adjustment spiral to hold the workpiece. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-011011 Summary of the Invention [Problem to be solved by the invention]

[0004] The scroll chuck has a drawback in that it moves forward a short distance with one rotation, and it takes a long time to hold a workpiece. The present invention has been made in view of the above circumstances, and its object is to provide a workpiece holding device that can quickly hold a workpiece. [Means for solving the problem]

[0005] The workpiece holding device of the present invention is a device for holding a workpiece, and includes a first rotating body having a first rolling body provided between a first inner ring and a first outer ring, a base stand that supports the first inner ring so that the first outer ring is rotatable, an actuator that rotates the first outer ring, a holding arm that is installed on the base stand so that it can move back and forth, and a transmission body that transmits the rotational force of the first outer ring to the holding arm. [Effects of the Invention]

[0006] The workpiece holding device of the present invention can move back and forth a longer distance than a conventional scroll chuck by simply extending and retracting the actuator, and therefore can hold the workpiece quickly. [Brief explanation of the drawings]

[0007] [Figure 1] 1A and 1B are perspective views showing an example of a workpiece holding device. [Figure 2] FIG. 2 is a perspective view showing an example of a workpiece holding device including a rotation mechanism and a hydraulic oil supply unit. [Figure 3] FIG. 3 is a detailed explanatory diagram of a first rotating body and a second rotating body. [Figure 4] 10(a) to 10(c) are detailed explanatory diagrams of the hydraulic oil supply unit. [Figure 5] 10(a) and 10(b) are explanatory diagrams of the operation of the hydraulic oil supply unit. [Figure 6] FIG. 10 is an explanatory diagram showing an example of a case where the workpiece holding device is mounted on a positioner. [Figure 7] FIG. 10 is a perspective view showing an example of a state in which a cylindrical workpiece is held. [Figure 8] FIG. 10 is a perspective view showing an example of a state in which an annular workpiece is held. DETAILED DESCRIPTION OF THE INVENTION

[0008] (Embodiment) An example of an embodiment of the present invention will be described with reference to the drawings. As an example, a workpiece holding device shown in Figures 1(a) and 1(b) includes a base table 11 that serves as the base of the workpiece holding device. The base table 11 in this embodiment has a substantially rectangular shape in a plan view, and is provided in the center with an opening 11a large enough to accommodate a workpiece W.

[0009] A rotating body (hereinafter referred to as the "first rotating body") 12 is provided on the periphery of the opening 11a of the base table 11. In this embodiment, a slewing bearing is used as the first rotating body 12, in which a rolling element 12c (first rolling element) is disposed between an outer ring (hereinafter referred to as the "first outer ring") 12a and an inner ring (hereinafter referred to as the "first inner ring") 12b. The first inner ring 12b is fixed to the base table 11, and the first outer ring 12a is designed to rotate without being fixed to the base table 11.

[0010] An outer peripheral gear (hereinafter referred to as "first outer peripheral gear") 13 that engages with a transmission gear 18 described below is provided on the outer periphery of the first outer ring 12a. The first outer peripheral gear 13 may be formed integrally with the first outer ring 12a, or may be a separate piece that is later attached to the first outer ring 12a. In the example shown in the figure, the first outer peripheral gear 13 is provided around the entire circumference of the first outer ring 12a, but the first outer peripheral gear 13 may also be provided partially around the outer periphery of the first outer ring 12a.

[0011] A mounting bracket 14 for mounting an actuator 15 is provided on the base 11. The mounting bracket 14 is a horizontally U-shaped member with two opposing pieces. The actuator 15 is disposed between the two opposing pieces and is supported by a support shaft so that it can rotate horizontally. Note that the rotation referred to here includes the rotation of the actuator 15 in forward and reverse directions around the support shaft as the axis of rotation as the actuator 15 expands and contracts.

[0012] In this embodiment, two mounting brackets 14 are provided, and an actuator 15 is attached to each mounting bracket 14. The number of mounting brackets 14 and actuators 15 may be more or less than two.

[0013] The actuator 15 is a means for rotating the first outer ring 12a. In this embodiment, hydraulic cylinders are used as both actuators. Both actuators 15 are designed to operate synchronously. Actuators other than hydraulic cylinders can also be used as the actuators 15. Actuators 15 other than hydraulic cylinders will be described later.

[0014] A fixed bracket 16 having an arc shape in plan view is provided at the tip of the rod 15a of each actuator 15. The fixed bracket 16 is fixed to the upper surface of the first outer ring 12a so that the power of the actuator 15 rotates the first outer ring 12a in forward and reverse directions.

[0015] A transmission gear 18 that transmits power to a holding arm 17 (described later) is provided at a position outside the first outer ring 12a on the upper surface of the base table 11. In this embodiment, four transmission gears 18 are provided at equal intervals along the first outer peripheral gear 13. Each transmission gear 18 is provided at a position where it engages with the first outer peripheral gear 13 and an arm gear 17a (described later).

[0016] Guide installation sections 11b for installing arm guides 19 are provided at the four corners of the base 11. Each guide installation section 11b is provided with an arm guide 19 extending toward the center of the base 11, and each arm guide 19 has a holding arm 17 slidably mounted thereon.

[0017] The holding arm 17 has an arm portion 17b extending toward the center of the base 11 and a holding portion 17c provided at the tip of the arm portion 17b. An arm gear 17a that engages with a transmission gear 18 is provided along the side of the arm portion 17b. The transmission gear 18 functions as the pinion in the rack and pinion mechanism, and the arm gear 17a functions as the rack.

[0018] In the work holding device configured in this manner, when the first outer ring 12a rotates in the forward direction due to the operation of the actuator 15, the rotational force causes the transmission gear 18 engaged with the first outer peripheral gear 13 to rotate, and the rotational force of the transmission gear 18 is transmitted to the arm gear 17a, causing the holding arm 17 to slide (move forward) toward the center of the base table 11.

[0019] On the other hand, when the holding arm 17 advances toward the center of the base stand 11 and the first outer ring 12a rotates in the opposite direction due to the operation of the actuator 15, the rotational force causes the transmission gear 18 engaged with the first outer peripheral gear 13 to rotate, and the rotational force of the transmission gear 18 is transmitted to the arm gear 17a, causing the holding arm 17 to slide (retreat) in a direction away from the center of the base stand 11.

[0020] The workpiece holding device of this embodiment can be used as is, but can also be mounted on a rotation mechanism 20 for use, as shown in Figures 2 and 3. By mounting it on the rotation mechanism 20, the orientation (posture) of the workpiece W held by the workpiece holding device can be changed, improving convenience.

[0021] The rotation mechanism 20 of this embodiment includes a fixed seat 21. The fixed seat 21 has a substantially rectangular shape in a plan view, and is provided with a fixed seat opening 21a in the center that is large enough to accommodate the workpiece W and is approximately the same size as the opening 11a of the base 11.

[0022] A second rotating body 22 is provided on the periphery of the fixed seat opening 21a. As with the first rotating body 12, in this embodiment, a slewing bearing is used as the second rotating body 22, in which a rolling element (second rolling element) 22c is disposed between an outer ring (hereinafter referred to as the "second outer ring") 22a and an inner ring (hereinafter referred to as the "second inner ring") 22b. The second inner ring 22b is fixed to the fixed seat 21, and the second outer ring 22a is designed to rotate without being fixed to the fixed seat 21.

[0023] An outer peripheral gear (hereinafter referred to as "second outer peripheral gear") 23 that engages with the rotary gear 24 is provided on the outer periphery of the second outer ring 22a. The second outer peripheral gear 23 is annular and is provided around the entire circumference of the second outer ring 22a. A base stand 11 is fixed to the upper side of the second outer ring 22a, and as the second outer ring 22a rotates, the base stand 11 rotates in the rotational direction of the second outer ring 22a.

[0024] A rotating gear 24 that transmits power to the second outer peripheral gear 23 is provided at a position outside the second outer ring 22a on the upper surface of the fixed washer 21. The rotating gear 24 is provided at a position where it engages with the second outer peripheral gear 23. The rotating gear 24 is connected to a motor (not shown) built into the fixed washer 21, and is rotated by the power of the motor.

[0025] When mounted on the rotation mechanism 20, it is necessary to ensure that the hose 33 for supplying hydraulic oil to the actuator 15 (hereinafter referred to as the "hydraulic hose") does not interfere with rotation. In this embodiment, the free rotation of the workpiece holding device is achieved by providing a hydraulic fluid supply unit (hereinafter referred to as the "hydraulic oil supply unit") 30 that can be switched between a disconnected state and a connected state.

[0026] As an example, the hydraulic oil supply unit 30 shown in Figures 4(a) to (c) and Figures 5(a) and (b) includes a detachable unit (first unit) on the base stand 11 side and a unit (second unit) on the fixed seat 21 side. The two units are connected when hydraulic oil is supplied to the actuator 15, and are separated when the base stand 11 side is rotated.

[0027] The unit on the fixed seat 21 side includes a lifting mechanism 31 provided on the fixed seat 21, a coupler plug 32 (first attachment / detachment device) provided on the lifting body 31b of the lifting mechanism 31, and a hydraulic hose 33 connected to the coupler plug 32.

[0028] The lifting mechanism 31 includes a linear guide 31a provided on the side of the fixed base 21, an L-shaped lifting body 31b that moves up and down along the linear guide 31a, and a lifting cylinder 31c that moves up and down the lifting body 31b. A hydraulic cylinder or the like can be used as the lifting cylinder 31c.

[0029] The lifting body 31b is provided with a two-port coupler plug 32, one of which is connected to a hydraulic hose for clamping (plug side clamping hose) 33a as a first hose, and the other is connected to a hydraulic hose for unclamping (plug side unclamping hose) 33b as a second hose.

[0030] The unit on the base 11 side includes a coupler plug 32 provided on the fixed seat 21 side, a detachable coupler socket 34 (second attachment / detachment device), and a hydraulic hose (fluid hose) 33 connected to the coupler socket 34. Like the coupler plug 32, the coupler socket 34 also has two ports, each connected to branch joints 35 and 36.

[0031] Both joints 35, 36 are of a bifurcated type, and a hydraulic hose for clamping (hereinafter referred to as the "socket side clamping hose") 33c as a first hose is connected to one joint 35, and a hydraulic hose for unclamping (hereinafter referred to as the "socket side unclamping hose") 33d as a second hose is connected to the other joint 36. The socket side clamping hose 33c and the socket side unclamping hose 33d are connected to the two actuators 15, respectively.

[0032] An accumulator 37 is connected to the middle of the socket-side clamp hose 33c via a bifurcated joint 38. The accumulator 37 maintains the force acting on the holding arm 17 to clamp (hold) the workpiece W when the first and second attachment / detachment tools are separated.

[0033] When hydraulic oil enters the inside of the accumulator 37, the gas inside the accumulator 37 is compressed, generating a pushing force, which acts on the holding arm 17 in a direction that clamps the workpiece W, thereby enabling the workpiece W to be securely held even when the coupler plug 32 and coupler socket 34 are separated.

[0034] In addition, in the work holding device of the above embodiment, a pressure sensor or the like can be provided on the holding arm 17 so that it is determined that holding of the work W is complete when the pressure on the holding arm 17 exceeds a predetermined threshold value.

[0035] In this case, a signal from the pressure sensor can be automatically sent to the hydraulic oil supply unit 30, and the hydraulic oil supply unit 30 can be operated based on the signal. Specifically, the lifting body 31b can be lowered by the operation of the lifting cylinder 31c, and the unit on the base stand 11 side and the unit on the fixed seat 21 side can be separated.

[0036] The separation of the unit on the base stand 11 side from the unit on the fixed seat 21 side stops the supply of hydraulic oil to the actuator 15. At this time, a force that clamps (holds) the workpiece W acts on the holding arm 17 due to the action of the accumulator 37 (the pushing back force generated in the accumulator 37), and the workpiece W is kept held.

[0037] In this case, it is possible to automate all or part of a series of processes, such as holding a workpiece, machining the held workpiece, changing the position of the workpiece during machining, moving the workpiece after machining is complete, and releasing the workpiece at the destination. Note that the machining referred to here includes all types of machining, such as welding, painting, finishing, assembly, and wiring.

[0038] The workpiece holding device of the present invention can be used by itself, or, as shown in Fig. 6, can be mounted on a positioner P that holds a workpiece W and changes the position and orientation of the workpiece W. The workpiece holding device can also be used as a jig attached to the tip of a crane.

[0039] In either case, the workpiece holding device can be mounted directly on the positioner P or attached to a crane, or it can be mounted on a rotation mechanism and then mounted on the positioner P or attached to a crane.

[0040] The configuration of the above embodiment is an example, and the configuration of the work holding device of the present invention is not limited to the configuration of the above embodiment. The work holding device of the present invention can be modified in various ways, such as by replacing, omitting, or adding components, within the scope of achieving the intended purpose. For example, the following modifications are possible.

[0041] -Variation 1- In the above embodiment, a hydraulic cylinder is used as the actuator 15 for rotating the first outer ring 12a, but the actuator 15 may also include other actuators than hydraulic cylinders, such as air cylinders, hydraulic motors, and gear motors, and these may also be used instead of hydraulic cylinders.

[0042] When a device using a fluid (liquid or gas) other than hydraulic pressure as a drive source is used as the actuator 15, a detachable hydraulic fluid supply unit (liquid supply unit or gas supply unit) similar to the hydraulic oil supply unit 30 of the above embodiment can be used. In this case, the term "hydraulic pressure" in the above embodiment should be read as "fluid," "liquid," or "gas (or air)."

[0043] When a hydraulic fluid supply unit 30 using hydraulic pressure as a drive source, such as a hydraulic motor, is used as the actuator 15, a hydraulic fluid supply unit 30 similar to the hydraulic oil supply unit 30 of the above embodiment can be used.

[0044] -Variation 2- In the above embodiment, an example is given in which the coupler plug 32 is provided on the unit on the fixed seat 21 side and the coupler socket 34 is provided on the unit on the base stand 11 side, but it is also possible to provide the coupler socket 34 on the unit on the fixed seat 21 side and the coupler plug 32 on the unit on the base stand 11 side.

[0045] (operation) Next, the operation of the workpiece holding device of the present invention will be described. First, the operation when holding a cylindrical workpiece W using the workpiece holding device shown in Figures 1(a) and 1(b) and the operation when holding an annular workpiece W will be described.

[0046] 1(a) and 1(b) is used to hold a cylindrical workpiece W, the workpiece W is placed in the opening 11a of the base table 11 with the holding arm 17 retracted, and the actuator 15 is operated. When the actuator 15 operates, the first outer ring 12a rotates in the forward direction, causing all of the transmission gears 18 engaged with the outer periphery gears 13 to rotate. When the transmission gears 18 rotate, the rotational force is transmitted to the arm gears 17a, and the holding arms 17 to which the arm gears 17a are fixed move forward. When the holding arms 17 move forward until the holding portions 17c of all of the holding arms 17 abut against the outer periphery of the workpiece W, the workpiece W is pressed by the inner circumferential surfaces of the holding portions 17c, and the workpiece W is held (FIG. 7).

[0047] On the other hand, when holding an annular workpiece W using the workpiece holding device shown in FIGS. 1(a) and 1(b), the holding arms 17 are advanced, and the workpiece W is placed across the arm portions 17b of the multiple holding arms 17, and the actuator 15 is operated. When the actuator 15 is operated, the first outer ring 12a rotates in the reverse direction, and all of the transmission gears 18 engaged with the peripheral gears 13 rotate. When the transmission gears 18 rotate, the rotational force is transmitted to the arm gears 17a, and the holding arms 17 to which the arm gears 17a are fixed move backward. When the holding arms 17 move backward until the outer peripheral surfaces of the holding portions 17c of all of the holding arms 17 abut against the workpiece W, the workpiece W is pulled by the outer peripheral surfaces of the holding portions 17c, and the workpiece W is held (FIG. 8).

[0048] Next, we will explain the operations performed when holding a cylindrical workpiece W using the workpiece holding device shown in Fig. 2. Here, we will explain the operations performed when holding the workpiece W, when rotating the held workpiece W, and when releasing the held workpiece W.

[0049] 2 is used to hold a cylindrical workpiece W, the lifting body 31b is raised by the lifting cylinder 31c, and the coupler plug 32 provided on the lifting body 31b is connected to the coupler socket 34 provided on the base table 11. In this state, when the actuator 15 is operated to rotate the first outer ring 12a in the forward direction, all the holding arms 17 move forward and the workpiece W is held.

[0050] When the workpiece W held by the holding arm 17 is to be rotated, the lifting body 31b is lowered by the lifting cylinder 31c, and the coupler plug 32 and the coupler socket 34 are separated. In this state, when the motor built into the fixed base 21 is operated, the power of the motor rotates the rotating gear 24, which in turn rotates the second outer ring 22a engaged therewith. When the second outer ring 22a rotates, the base table 11 and the holding arm 17 mounted on the base table 11 rotate, and the workpiece W held by the holding arm 17 rotates in accordance with this rotation.

[0051] When the workpiece W held by the holding arms 17 is to be released, the lifting body 31b is raised by the lifting cylinder 31c, and the coupler plug 32 provided on the lifting body 31b is connected to the coupler socket 34 provided on the base table 11. In this state, when the actuator 15 is operated to rotate the first outer ring 12a in the reverse direction, all the holding arms 17 are retracted, and the workpiece W held by the holding arms 17 is released. [Industrial Applicability]

[0052] The workpiece holding device of the present invention can be used to hold various types of workpieces W, and is particularly suitable for holding columnar, cylindrical, or annular (ring-shaped) workpieces W. [Explanation of symbols]

[0053] 11 Base 11a opening 11b Guide installation section 12 First Rotating Body 12a Outer ring (first outer ring) 12b Inner ring (first inner ring) 12c Rolling element (first rolling element) 13 Peripheral gear (first peripheral gear) 14 Mounting bracket 15 Actuators 15a Rod 16 Fixing bracket 17 Holding arm 17a Arm Gear 17b Arm part 17c Holding part 18 Transmission gear 19 Arm guide 20 Rotation mechanism 21 Fixed seat 21a Fixed seat opening 22 Second Rotating Body 22a Outer ring (second outer ring) 22b Inner ring (second inner ring) 22c Rolling element (second rolling element) 23 Peripheral gear (second peripheral gear) 24 Rotating gear 30 Hydraulic oil supply unit (hydraulic fluid supply unit) 31 Lifting mechanism 31a Linear guide 31b Elevator 31c Lifting cylinder 32 Coupler plug (first attachment / detachment device) 33 Hydraulic hose (fluid hose) 33a Plug side clamp hose (first hose, first hydraulic hose) 33b Plug side unclamping hose (first hose, first hydraulic hose) 33c Socket side clamp hose (second hose, second hydraulic hose) 33d Socket side unclamping hose (second hose, second hydraulic hose) 34 Coupler socket (secondary attachment / detachment tool) 35 Joints 36 Joints 37 Accumulator 38 Joints P Positioner double work

Claims

1. In a work holding device for holding a work, a first rotating body in which a first rolling element is provided between a first inner ring and a first outer ring; a base supporting the first inner ring so that the first outer ring is rotatable; an actuator that rotates the first outer ring; a holding arm that is installed on the base table so as to be able to move forward and backward; a transmission body that transmits the rotational force of the first outer ring to the holding arm, A workpiece holding device characterized by:

2. 2. The workpiece holding device according to claim 1, a mounting bracket for mounting the actuator on the base; The actuator is rotatably attached to the mounting bracket. A workpiece holding device characterized by:

3. 2. The workpiece holding device according to claim 1, a first outer peripheral gear is provided on the outer periphery of the first outer ring; the transmission body includes a transmission gear that meshes with the first outer peripheral gear; The holding arm has an arm gear that meshes with the transmission gear. A workpiece holding device characterized by:

4. 2. The workpiece holding device according to claim 1, a second rotating body in which a second rolling element is provided between the second inner ring and the second outer ring; a fixed seat that supports the second inner ring so that the second outer ring is rotatable; A rotation gear that rotates the second outer ring is provided. A workpiece holding device characterized by:

5. 5. The workpiece holding device according to claim 4, a working fluid supply unit that supplies fluid to the actuator as a driving source; the working fluid supply unit includes a detachable first unit and a detachable second unit; The first unit is provided on a base stand, The second unit is mounted on a fixed seat. A workpiece holding device characterized by:

6. 6. The workpiece holding device according to claim 5, the first unit includes a first attachment / detachment device; the second unit includes a second attachment / detachment tool, a lifting cylinder, and a lifting body; The second attachment / detachment tool is provided on the lifting body, The first detachable tool and the second detachable tool are attached and detached in accordance with the elevation of the lifting body by the lifting cylinder. A workpiece holding device characterized by:

7. 7. The workpiece holding device according to claim 6, the first unit includes a first hose connected to the actuator; the second unit includes a second hose connected to the drive source; a first attachment / detachment tool connected to the first hose; A second attachment / detachment tool is connected to the second hose. A workpiece holding device characterized by:

8. The workpiece holding device according to claim 7, an accumulator is connected to the first hose, the accumulator maintaining a force acting on the holding arm to hold the workpiece when the first attachment / detachment tool and the second attachment / detachment tool are separated; A workpiece holding device characterized by:

Images